Isaac grew up on a farm in Catawba, North Carolina on the second youngest of nine children. He left school after the sixth grade, which mistakenly led to the rumor that he could neither read nor write.
Isaac began with the professional racing in 1956, but took seven years to advance to the Grand National series of NASCAR. He won in the 1970 season the championship in Dogde Charger Daytona with the start number 71, together with his crew chief Harry Hyde he exhibited at the Talladega Superspeedway in November 1970 set a speed record on a closed race track on.
During his career in the top racing series of NASCAR Isaac won a total of 37 races, including eleven in his championship season in 1970. Moreover, in the 1969 season, he scored 50 pole positions, of which alone 20, which is equipped with state of 2007 is still a record. Isaac stepped back from racing because a voice inside him said to have warned that he will die, he would drive more races.
Bobby Isaac died on 14 August 1977, when he got in a race to the Late Model Sportsman Series at the Hickory Motor Speedway 25 laps from the finish of the race and died of a heart attack.